About this Abstract |
Meeting |
2022 Annual International Solid Freeform Fabrication Symposium (SFF Symp 2022)
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Symposium
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2022 Annual International Solid Freeform Fabrication Symposium (SFF Symp 2022)
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Presentation Title |
Laser Powder Bed Fusion of Defect-Free NiTi Shape Memory Alloy Parts with Superior Mechanical Response |
Author(s) |
Abdelrahman Rashed Mohmaed Elsayed, Ibrahim Karaman, Kadri Can Atli, Raymundo Arroyave, Alaa Elwany, Chen Zhang, Lei Xue |
On-Site Speaker (Planned) |
Abdelrahman Rashed Mohmaed Elsayed |
Abstract Scope |
Laser powder bed fusion (L-PBF) is a promising additive manufacturing (AM) technique for the fabrication of NiTi shape memory alloy (SMA) parts with complex geometries that are otherwise difficult to fabricate through traditional processing methods. In this study, NiTi parts were fabricated using L-PBF and consistently exhibited room temperature tensile superelasticity up to 6% in the as-printed condition, almost twice the maximum reported value in the literature. The use of optimized processing parameters, carefully tailoring the evaporation of Ni from a Ni-rich NiTi powder feedstock, and controlling the printing chamber oxygen content eliminated porosity and cracks. Crystallographic texture analysis demonstrated that the as-printed NiTi parts had a strong preferential texture for superelasticity. Transmission electron microscopy investigations revealed the presence of nano-sized oxide particles and Ni-rich precipitates in the as-printed parts, which play a role in the improved SE by suppressing inelastic accommodation mechanisms for martensitic transformation. |
Proceedings Inclusion? |
Definite: Post-meeting proceedings |